Was a pretty great short experience. Had a few good challenging levels to get the coins.
The main frustration was hit boxes size on the alien ships seemingly large and the platforms being small.
This concept would work very well with upgradable components (more coins) that allow the player to make more difficult movements, take hits, bounce off the surface. Teather to save from a screw up. Single life, but keep your upgrades. Each round gets more difficult. Moving enemy types etc.